A video photographing apparatus such as a camera may be installed on a flight system such as an unmanned aerial vehicle, for obtaining video data. The video data needs to be transmitted in real time to a receiving and display apparatus such as a remote control. During this process, various steps of video image frame acquisition, compression encoding, wireless transmission, wireless reception, compression decoding, display, etc. may be needed. The time needed for completing this process should be as short as possible, so as to reflect a current flight situation in time to avoid accidents.
The video data includes a plurality of successive image frames. The camera acquires the video image at a fixed frame rate and continuously sends it to the remote control for display. The user will see dynamic video pictures. At present, most of the cameras are configured to use the same frame rate as that used at a display side, i.e., the remote control, for acquiring the video image. That is, the camera's acquisition frame rate is equal to the display's display frame rate, thus a delay introduced by acquisition time determines the delay introduced by display time, which eventually results in a larger video image transmission delay.